Hi Paul & All,
12a Single Rotor now has 5.5 Hrs. Run time,
Listed changes made during runs to present con-fig.
1. Re-Key E-Shaft to Psru Sun Gear
2. Prop is 60 in. 3 blade now with 20 degree pitch
3. Mikuni 38mm carb. with 25 in. x 1 3/4 Dia.runner
4. Installed EGT seeing 1600 degrees at 5000 RPM,
Exhaust system is no longer red hot
5. Installed Auto Tach, back-up to Rotax Tach/Hobbs
6. Timing is @ 20 degrees BTDC both plugs
7. Throttle now able to go WOT
During the last run 5800 rpm I went to WOT, I had small fuel mist
cloud form at the
carb. bell mouth, is this related to runner length? I'm preparing a
Mikuni 40mm carb.
>>see
http://www.youtube.com/watch?v=Hh_v25dAzc0
12a Single Rotor Run68 Bell mouth Fuel Mist
I took some measurements to help Identify the Psru gear set.
Planetary Carrier, 5.60 in. OD.x 3.5 in. ID, 6 pinions 14 tooth x
1in wide
Planetary Shaft, 1.87 in. dia. with keyway for prop hub
Ring Gear, 5.7 in.ID x 1.25 in. wide, 59 tooth Inside & Outside,
.525in. thick
Sun Gear, 3.285 in. OD x 1.85 wide, 31 tooth
Would appear that the planetary carrier extends thru the most forward
bearings and that the prop hub is pressed on,without
positive retention, the planetary shaft has (3/4 16 Not) 18mm tapped
hole.
Before additional runs I will add a retainer washer and bolt.
>> Washer & Retainer bolt now Installed.
Video last Run
http://www.youtube.com/watch?v=wsw3QbDCid8
Paul & All,
Have added Scale to Eng.stand to monitor Static Thrust,
The 12a Single Rotor @ 6000rpm indicates approx.210lb.
This compares with my KitFox Rotax 582/65hp 6500rpm approx. 230lb
We seem to be getting about 1/2 stock 12A hp @ 1 liter/10th.hr. fuel
consumption?
Video
http://www.youtube.com/watch?v=hFlZcVe1PXc
12a Single Rotor Run67
Looking for something like MegaJolt to do the Edis/Saw input,
http://www.bgsoflex.com/mjl/mjl_edis_stim.html
Best Regards
Rolland (Philippines)
KitFoxes RP-S135/S2804
Don't get too carried away optimizing for static thrust. Static thrust is
interesting but what you really want is max thrust at take off and climb
speeds. That implies a bit more prop pitch than that needed for best static
thrust. Static thrust is largely a function of prop pitch and prop
diameter. The larger the diameter the more static thrust. 60 inch diameter
is on the low side. People have died relying on static thrust readings alone.
I just invented a cheaper dyno made from garage door springs.
You can also use bath room scales if the total weight of your rig
is less than about 600 pounds. Bathroom scales are limited to about 300
pounds each. You may need to calibrate the garage door
springs by measuring the deflection as a function of weight added.
Then measure the length of the springs when the engine is flat out.
You know the torque and rpm you know the HP.
HP = (T x RPM)/5252. You can safely use a linear extrapolation
for P-port rotary engines. Lets say you have 100 HP at 5800 RPM static.
at 6500 RPM you will have 6500/5800 x 100 HP or 112 HP.
What is the gear ratio of that planetary?
6000 RPM is rather low. Half of a stock 12A HP is low
for a P-port.
The mist stand off on the carb is normal.
You will need a ram airbox to contain that.
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Is that a true P-port engine Rolland or is it a box manifold
feeding the side ports?
Paul Lamar
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